Starter shim or weak battery?

So I am finally finished with the engine compartment, everything hooked up---I am trying the initial start up--when I was testing the starter without ignition, it turned over the engine fine. But when I turn on all the accessories (fuel pump, water pump, fan, etc), I can hear the fuel pump motor speed change when I turn on the other accessories, which leads me to believe my battery may be charged, but maybe fails under load---

So when I turn on the ignition, the starter struggles to turn the motor over, then it kicks back and grinds. I had one person tell me that since it doesn't do that with the ignition off, its most likely a weak battery. I plan on going with a 16 V battery anyway. I also have an MSD 7AL-3, and have the start retard hooked up.

So my question is---is it possible if the starter sounds like its not engaging correctly be the result of a weak battery (has anyone heard of that) or do I need to take the starter off and shim it? When the battery was fresh with no ignition, it turned over fine. But now, it grinds and doesn't sound right at all.

Here is my set up, oh and its a Hitachi mini starter, 2.68 hp-

I had a 16v, it took a dump when I went to start the car a couple weeks ago................I put a 12v deal I had lying around and it cranks it just as good.

In other words 12v should do the trick, not sure how yours is all wired.......my stuff is top notch on the electrical though.

How are the main battery cables set up on yours?

Is it a new starter? It is possible that it is drawing to many amps. There are a lot of people who chase starting problems only to find out that the starter really isn't in very good condition or up to the task.

also as you said the battery may be bad, and FWIW I use one of the factory gear reduction staters like off of the 1995 F series trucks.

Also you need to check the rotor phase.

Was there a thread on rotor phase awhile back ? I need to reread about it !

Mark

question is where is your ground cable run too is it run to the frame or to the engine ? A chassls guy once explained that you are trying to start an engine not the frame of your race car so the cable needs to be ran all the way to the engine for best results...... you also say you have a MSD 7al3 do the starter retards have a zero chip in them? if not the will be way off..... just a suggestion....

The starter is brand new, its a Hitachi high torque mini starter, 2.68hp motor, supposedly good for an 18:1 motor----I have 3 grounds, all though the battery in the trunk is grounded to the frame---but I have the block grounded to the frame in two spots.

Can you provide a link to what you mean by "rotor phase"? I need to read up on that-

imo rotor phase is not your problem because you mentioned the other accessories pulled down.If they all have relays they should'nt pull down w/16V battery. have you tried spinning it first and then hitting the ignition switch?

Rotor out of phase can be a definate issue, more so if he is using a start retard. One way to confirm this is crank the engine with ign off.....................if it spins fine then I'd for sure check it. If its jumping to a cyl early in the firing sequence its just like trying to start one with a shitload of initial in it.................will tear up starter drives, flywheels etc.

You may try switching the wires on your trigger pick up. You usually have to run them opposite in color, it'll make about 40 degrees difference in timing.No matter where you set the timing at with the trigger ,you'll never know where it actually is until you get it started and put a timing light on it. It sounds like your timing may be way high.Kicking back like that is a good indication the timing is way off.You can still phase your rotor a half turn out with a trigger.

Also make sure the dizzy is locked since you are using a crank trigger.

To check rotor phase drill a 3/8" hole in the dist cap between the coil and the #1 terminal. Paint a small white line on the rotor strap where it is visible through the hole. Start engine and use a timing light to check rotor alignment through the hole. If its off turn the dizzy until it is centered.

psfracer wrote:The starter is brand new, its a Hitachi high torque mini starter, 2.68hp motor, supposedly good for an 18:1 motor----I have 3 grounds, all though the battery in the trunk is grounded to the frame---but I have the block grounded to the frame in two spots.Can you provide a link to what you mean by "rotor phase"? I need to read up on that-

Here is case in Point are you trying to start your Car or your engine? The ground wire should be grounded to the frame and one going from the Battery to the engine not having any frame contact.....

Thanks for the feedback everyone.

I am going to assume the timing is ok as the engine came right off of the dyno--set at 30 degrees total. HOWEVER---it is possilbe I suppose that I have it set up 180 degrees out.

Just a quick confirmation, to find TDC I spun the engine until both valves closed on cylinder #1 (passenger front cylinder). The TDC I used was when, before TDC, the intake valve was open--so it shouldn't be 180 degrees out?

As far as the ground for the battery, can I use a 4 gauge (vs a 1 or 0 guage)--when routing it to the block directly?

again how does it crank with the ign off?

again how does it crank with the ign off?

It cranks over fine with the ignition off which would point to ignition timing. I am going to try another battery to eliminate that---as I was going to go with a 16V battery anyway as I am not running an alternator. If it is a weak battery (under load) even if the ignition timing was correct wouldn't the engine be harder to start?

In any case I am checking to make sure I didn't put the ignition wiring 180 degrees out first as soon as I get home today.

psfracer wrote:It cranks over fine with the ignition off which would point to ignition timing. I am going to try another battery to eliminate that---as I was going to go with a 16V battery anyway as I am not running an alternator. If it is a weak battery (under load) even if the ignition timing was correct wouldn't the engine be harder to start?

In any case I am checking to make sure I didn't put the ignition wiring 180 degrees out first as soon as I get home today.

settles that......................fire it up and verify the ign timing, if they used a different box for the dyno they can vary. Make sure the rotor is locked as you dont need it moving with the advance springs. Then check the rotor phase...................